Human Genetics
Chapters 11 & 12
Genetic Disorders:
Autosomal disorder=
-inheritable (due to a defective gene)
-not a disease/not contagious
-cannot be prevented
-no cure
-can be treated to some degree
-normal=
-carrier=
-affected=
-recessive disorder=
-dominant disorder=
Recessive Disorders
1. Cystic Fibrosis
Symptoms=
1/20 heterozygous=
1/3000 homozygous=
2. Sickle Cell Disease (Anemia)
-also incomplete dominance
-symptoms
1/11 heterozygous=
(Sickle Cell Trait)
1/500 homozygous=
3. Tay-Sachs Disease
-symptoms
1/3600 homozygous
4. Phenylketonuria
-symptoms
1/5000 homozygous
Dominant Disorders
1. Neurofibromatosis
-symptoms
1/3500 homozygous
2. Huntingdon Disease
symptoms
1/20,000 homozygous
Sex Linked or X-Linked Disorders:
Human Chromosome # =
Autosomes=
Sex Chromosomes=
XX=
XY=
Who determines sex of offsping?
-Patterns of X-linkage=
-inheritable (due to a defective gene)
-not a disease/ not contagious
-cannot be prevented
-no cure
-can be treated to some degree
Types:
1. Color Blindness
-8% of caucasion males
2. Muscular Dystrophy
1/3600 males
3. Hemophilia
1/10,000 males
-symptoms
4. Fragile X Syndrome
1/1500 males 1/2500 females
Aneuploid Disorders:
-Not inheritable (do not run in familes)
-not a disease/not contagious
-no cure/can be treated to some degree
-due to an improper # of c’somes
-Euploid=
-Aneuploid=
How do these occur?
Disjunction=
Nondisjunction=
What causes this to happen?
Types:
1. Monosomy=
2. Trisomy (Polyploidy)=
3. Trisomy 21=
Sex Chromosome Disorders
1. Additional X:
a. XXX (Poly-X)=
XXXX
b. XXY (Klinefelter Syndrome)=
XXXY
2. Loss of X:
a. OX (Turner Syndrome)=
b. OY=
3. Additional Y = XYY
(Jacobs Syndrome)
Chromosomal Abnormalities:
1.) Deletion Syndromes=
-Williams Syndrome=
-Cat’s Cry Syndrome=
2.) Translocation Syndromes=
-Alagille Syndrome=